Depends on the model I guess.
Our Carefree is adjustable. There is a push tab on either arm with several holes for setting. I find it easier to adjust when retracted; actually I can only do it when retracted, but Carefree says you can do it extended too. Push in the button and slide the inner frame arm up or down to the desired position. You can also set an angle side to side, but don't put a difference of more than 3 positions (holes).
We didn't have any instructions with our TT when purchased, but the instructions were pretty easy to find on the Carefree site. And this is on a TT, not Class C, but they look to operate fairly similarly.
2011 Jayco X19H (purchased 2015)
2008 Jayco 1007 PUP (purchased new, traded for the X19)
2012 Chev Traverse LT with TP